serious, sometimes fatal events, such as infections, lymphoma, or other types of cancer, have happened. blood, liver and nervous system problem serious allergic reactions and new or worsening heart failure have occurred. before starting humira , your doctor should test you for tb. ask your doctor if you live in or have been to a region where certain fungal infections are common. tell your doctor if you have had tb, hepatitis b, are prone to infections, have symptoms such as fever fatigue, cough, or sores. you should not start humira if you have any kind of infection. ask your doctor if humira can work for you. this is humira at work.